xref: /freebsd/tests/sys/cddl/zfs/bin/largest_file.c (revision 580d00f42fdd94ce43583cc45fe3f1d9fdff47d4)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"@(#)largest_file.c	1.3	07/05/25 SMI"
28 
29 #include "file_common.h"
30 #include <sys/param.h>
31 #include <signal.h>
32 #include <stdio.h>
33 
34 /*
35  * --------------------------------------------------------------
36  *
37  *	Assertion:
38  *		The last byte of the largest file size can be
39  *		accessed without any errors.  Also, the writing
40  *		beyond the last byte of the largest file size
41  *		will produce an errno of EFBIG.
42  *
43  * --------------------------------------------------------------
44  *	If the write() system call below returns a "1",
45  *	then the last byte can be accessed.
46  * --------------------------------------------------------------
47  */
48 static void	sigxfsz(int);
49 static void	usage(char *);
50 
51 int
52 main(int argc, char **argv)
53 {
54 	int		fd = 0;
55 	off_t		offset = (OFF_MAX - 1);
56 	off_t		lseek_ret = 0;
57 	int		write_ret = 0;
58 	int		err = 0;
59 	char		mybuf[5];
60 	char		*testfile;
61 
62 	if (argc != 2) {
63 		usage(argv[0]);
64 	}
65 
66 	(void) sigset(SIGXFSZ, sigxfsz);
67 
68 	testfile = strdup(argv[1]);
69 
70 	fd = open(testfile, O_CREAT | O_RDWR);
71 	if (fd < 0) {
72 		perror("Failed to create testfile");
73 		err = errno;
74 		goto out;
75 	}
76 
77 	lseek_ret = lseek(fd, offset, SEEK_SET);
78 	if (lseek_ret < 0) {
79 		perror("Failed to seek to end of testfile");
80 		err = errno;
81 		goto out;
82 	}
83 
84 	write_ret = write(fd, mybuf, 1);
85 	if (write_ret < 0) {
86 		perror("Failed to write to end of file");
87 		err = errno;
88 		goto out;
89 	}
90 
91 	offset = 0;
92 	lseek_ret = lseek(fd, offset, SEEK_CUR);
93 	if (lseek_ret < 0) {
94 		perror("Failed to seek to end of file");
95 		err = errno;
96 		goto out;
97 	}
98 
99 	write_ret = write(fd, mybuf, 1);
100 	if (write_ret < 0) {
101 		if (errno == EFBIG) {
102 			(void) printf("write errno=EFBIG: success\n");
103 			err = 0;
104 		} else {
105 			perror("Did not receive EFBIG");
106 			err = errno;
107 		}
108 	} else {
109 		(void) printf("write completed successfully, test failed\n");
110 		err = 1;
111 	}
112 
113 out:
114 	(void) unlink(testfile);
115 	free(testfile);
116 	return (err);
117 }
118 
119 static void
120 usage(char *name)
121 {
122 	(void) printf("%s <testfile>\n", name);
123 	exit(1);
124 }
125 
126 /* ARGSUSED */
127 static void
128 sigxfsz(int signo)
129 {
130 	(void) printf("\nlargest_file: sigxfsz() caught SIGXFSZ\n");
131 }
132